oil seeping from final drive.

[AndyMac]

Hey up, went to Misano GP and came back last wednesday to find an oil puddle under final drive, seem to be coming from the big o-ring seal. I've topped up the FD it had lost 60mm, question. does that sound like it?, I cant find any other oil on the bike other than bottom of the FD, could it be coming via the gearbox ?
I've got a rebuild kit for the FD, I'm hoping when at Rainbow workshop on OCt4th for service Steve can take a look, I'm hoping its not the seal inside near the crown bearing?
Should I check the gearbox level?
TIA
Andy

 

[AndyMac]

UPDATE-

 

[AndyMac]

Update- half way to work this morn and thought I had a puncture then the dreaded crunching from back end, Im guessing the crown bearing has shit the bed?

 

[Greg Masters]

The large outer bearing is a known weakness. When it goes, it takes the seal with it.

You really shouldn’t ride the bike until it’s fixed - an easy DIY job.

 

[AndyMac]

do you mean the crown bearing?, I have a full rebuild kit, gonna nurse it 4 miles to the garage after work

 

[Greg Masters]

There are two bearings - a small inner bearing and a large bearing that is closest to the wheel. It is the large bearing that fails.

Riding home, you are likely to have all the oil from your final drive spread onto your rear tyre.

If it’s already leaking, I wouldn’t ride it anywhere.

 

[AndyMac]

There are two bearings - a small inner bearing and a large bearing that is closest to the wheel. It is the large bearing that fails.

Riding home, you are likely to have all the oil from your final drive spread onto your rear tyre.

If it’s already leaking, I wouldn’t ride it anywhere.

thanks

 

[kennyc]

from experience, its a couple of hours work for a muppet like me to do, just change the large bearing and seal, you will need a 7mm allen and either a suitable puller or a couple of slim cold chisels (I can hear the shocked gasps but it works perfectly well ) as well as the other bits I would get the large O'ring and a new seal for the ABS sensor (mine got clouted when the bearing collapsed and cut the O'ring when I removed the sensor) you may also need new pads for the back brake if the oil has got into it

 

[Paul Young]

Feeling like a flat tyre was exactly how mine felt a couple of years ago. The big bearing had gone in a spectacular way so I replaced both bearings, the large seal and the FD cover o-ring. I didn’t even need to remove the FD from the bike to do it, but used the freezer and oven to chill the crown wheel and heat the bearings before putting them together.

 

[AndyMac]

update on the update, it was the crown bearing, garage have stripped it and i delivered a full rebuild kit this morn, so hopefully back on the road soon rather than the train, bike had only done 36k

 

[KMD]

update on the update, it was the crown bearing, garage have stripped it and i delivered a full rebuild kit this morn, so hopefully back on the road soon rather than the train, bike had only done 36k

I think mine was at a similar mileage when it went in the Dolomites some years ago. Being so far from home with no tools as such, I had to have a dealer fix it. When we got back I replaced my brothers bearing just as a precautionary measure. Wasn’t difficult, a bit of cold/heat as Paul Young mentions above saw the new bearing slip on nicely.

 

[AndyMac]

I think mine was at a similar mileage when it went in the Dolomites some years ago. Being so far from home with no tools as such, I had to have a dealer fix it. When we got back I replaced my brothers bearing just as a precautionary measure. Wasn’t difficult, a bit of cold/heat as Paul Young mentions above saw the new bearing slip on nicely.

should have know really as my first 1150 did this at 50k nine years ago "!

 

[AndyMac]

update on the update on the update ----
all sorted, full rebuild kit fitted , porb not needed the full kit but thought best anyway) the CWB ring had disintegrated in parts and some of it fell out when he drained the FD lol. Makes me wonder cos, a month ago after I fitted a hugger, then I could hear a sort of aircraft whining sound possibly from the back, checked hugger etc and its was fine.
I'm wondering if that was the first indication that the bearing was on its way out?(it was before the oil leak).
I only had handling issues as the bearing was actually disintegrating.(all loose and weird at back like a R puncture, then followed by the crunch very shortly afterward at every wheel rotation) Anyway I'm back on the road again thank God as its my only transport.
I'm going to buy another kit as a spare again when funds allow.
thanks for all the replies